"Dementia is a terminal illness," study lead author Dr. Susan Mitchell of the Hebrew SeniorLife Institute for Aging Research in Boston, an affiliate of Harvard Medical School, says in a statement.
"As the end of life approaches, the pattern in which patients with advanced dementia experience distressing symptoms is similar to patients dying of more commonly recognized terminal conditions, such as cancer," she said.
The study, published in the New England Journal of Medicine, describes the clinical course of advanced dementia and suggests dementia patients need improved palliative care to reduce physical suffering.
The researchers studied 323 nursing home residents with advanced dementia living in 22 Boston-area nursing homes for up to 18 months.
The study finds 96 percent of the patients' healthcare proxies said comfort care was the primary goal of care for their loved one.
However, nearly 41 percent of those patients dying during the study underwent at least one intervention -- such as hospitalization or tube feeding -- in the last three months of life.
Notable deaths of 2014 [PHOTOS]